Pulley apparatus with built-in roller clutch and assembly method thereof

ABSTRACT

Excellent durability and reliability are provided and assembling work is made easy.  
     The clutch retainer  28   a  of the roller clutch  10   a  is prevented from being displaced in the axial direction. It is prevented that part of the clutch retainer  28   a  rubs the portion rotating together with the follower pulley  7   a , so that the heat generation during over-run is prevented. Accordingly, grease degradation is prevented, and durability and reliability are improved. In addition, the inner clutch ring  21  of the roller clutch  10   a  and the rollers are provided with a chamfered portion along the outer periphery at the end thereof in the axial direction. Accordingly, the rollers  26  are positioned properly in the circumferential direction, while the inner clutch ring  21  is easily installed on the inner diameter side of the rollers  26,  and the assembling work is made easy.

FIELD OF THE INVENTION

[0001] This invention relates to an improvement in a pulley apparatuswith built-in roller clutch for the auxiliary equipment drive of anengine, and its assembly method, for example used as a follower pulleythat is fastened to an end of the rotating shaft of the alternator in anautomobile generator, or as a drive pulley that is fastened to an end ofthe crank shaft of an automobile engine.

BACKGROUND OF THE INVENTION

[0002] The construction of an alternator for generating the requiredelectrical power for an automobile and which functions as the drivesource for the automobile engine is disclosed, for example in Japanesepatent publication No. Toku Kai Hei 7-139550. FIG. 1 shows thealternator 1 that is described in this publication. A pair of rollingbearings 4 supports the rotating shaft 3 inside the housing 2 such thatit rotates freely. There is a rotor 5 and a commutator 6 in the middlesection of this rotating shaft 3. Also, a follower pulley 7 is fastenedto the portion on one end (right end in FIG. 1) of the rotating shaft 3that protrudes outside the housing 2. When installed in the engine,there is an endless belt that extends around this follower pulley 7 suchthat the engine can freely drive the rotating shaft 3 by way of thecrankshaft.

[0003] Typically, a follower pulley that was simply fastened to therotating shaft 3 was used as the follower pulley 7. However, in recentyears, various kinds of pulley apparatuses with built-in one-wayclutches have been proposed and used in some applications, by whichpower is freely transmitted to the rotating shaft from the endless beltwhen there is a tendency for the running speed of the endless belt to beconstant or accelerating, and where the follower pulley and rotatingshaft rotate freely relative to each other when there is a tendency forthe running speed of the endless belt to be decelerating. For example, apulley apparatus with built-in one-way clutch having this kind offunction has been disclosed in Japanese patent publication Nos. Toku KaiHei 10-213207, Toku Kai Hei 10-285873, Toku Kai Hei 11-22753 and TokuKai Hei 11-63026. Also, the use of a roller clutch as the one-way clutchhas been known previously and has been disclosed in the aforementionedpublications.

[0004]FIG. 2 to FIG. 6 show a conventional pulley apparatus with thebuilt-in roller clutch as described in these publications. This pulleyapparatus with built-in roller clutch has a sleeve 8, which is a shaftmember (rotating shaft member) that can be fitted and fastened onto therotating shaft 3 of the alternator 1 (see FIG. 1). Also, the followerpulley 7 a which is a pulley member is located around this sleeve 8 suchthat it is concentric with the sleeve 8. Moreover, a pair of ballbearings 9 and a roller clutch 10 are located between the outerperipheral surface of the sleeve 8 and the inner peripheral surface ofthe follower pulley 7 a.

[0005] The sleeve 8 is shaped generally in a semi-cylindrical shape, andfitted onto and fastened around the end of the rotating shaft 3 of thealternator 1 such that it rotates together with the rotating shaft 3.Accordingly, in the example shown in the figures, a screw hole section11 is formed in the middle section on the inner peripheral surface ofthe sleeve 8, such that this screw hole section 11 can screw togetherwith the male screw section formed on the outer peripheral surface onthe tip end of the rotating shaft 3. Moreover, a fastening hole section12 having a hexagonal-shaped cross section is formed on the tip end(left end in FIG. 2) on the inner peripheral surface of the sleeve 8, sothat the tip end of a tool such as a hexagonal-shaped wrench can befastened to the fastening hole section 12. Furthermore, the base end(right end in FIG. 2) on the inner peripheral surface of the sleeve 8 isa circular hole section 13 into which the middle of the tip end of therotating shaft 3 can be fitted with no play therebetween. A splinejoint, non-circular joint, key joint or other construction can be usedas the construction for ensuring that there is no relative rotationbetween the sleeve 8 and the rotating shaft 3 in combination. Also, thecenter section of the outer peripheral surface of the sleeve 8 is alarge-diameter section 14 that has a larger diameter than the othersections.

[0006] On the other hand, the tip end half of the outer peripheralsurface of the follower pulley 7 a has a wave-shaped cross section inthe width direction, around which part of an endless belt called a polyV-belt extends. Also, the roller clutch 10 is located in the middlesection in the axial direction of the space that exists between theouter peripheral surface of the sleeve 8 and the inner peripheralsurface of the follower pulley 7 a, and there are ball bearings 9 thatare located near the opposite ends in the axial direction of this spacesuch that they are located on both sides in the axial direction of theroller clutch 10.

[0007] Of these parts, the ball bearings 9 support both radial loads andaxial loads that are applied to the follower pulley 7 a, and allow thefollower pulley 7 a to rotate freely with respect to the sleeve 8. Eachof the ball bearings 9 comprises: an outer race 16 that has adeep-groove type outer-ring raceway 15 formed around its innerperipheral surface; an inner race 18 that has a deep-groove typeinner-ring raceway 17 formed around its outer peripheral surface; and aplurality of balls 19 that are located between the aforementionedouter-ring raceway 15 and inner-ring raceway 17 such that they rollfreely. Also, the outer races 16 are fitted around the inner peripheralsurface near the opposite ends of the follower pulley 7 a, and the innerraces 18 are fitted around the outer peripheral surface near theopposite ends of the sleeve 8. Moreover, in this state, one of thesurfaces in the axial direction of each of the inner races 18 comes incontact with one of the opposite end surfaces (stepped surfaces) in theaxial direction of the large-diameter section 14, respectively. Inaddition, the openings on the opposite ends of the space where the balls19 are located are covered by seal rings 20 placed between the innerperipheral surfaces on the opposite ends of the outer races 16 and theouter peripheral surfaces on the opposite ends of the inner races 18.

[0008] Moreover, the roller clutch 10 transmits rotation force betweenthe follower pulley 7 a and the sleeve 8 only when there is a tendencyfor the follower pulley 7 a to rotate in a specified direction withrespect to the sleeve 8. In order to construct this kind of rollerclutch 10, the inner clutch ring 21 is fitted onto and securely fastenedaround the large-diameter section 14 of the sleeve 8 throughinterference fit. This inner clutch ring 21 is made of carburized steelplate or the like and formed into a cylindrical shape by plasticprocessing such as pressing, and a cam surface 22 is formed around itsouter peripheral surface. In other words, as shown in FIG. 3 and FIG. 5,by forming a plurality of concave sections 23, called the ramp section,at uniform intervals in the circumferential direction around the outerperipheral surface of the inner clutch ring 21, the outer peripheralsurface is able to function as the cam surface 22. In the example shownin the figures, a tapered, concave chamfered section 24 is formed on oneend (right end in FIG. 2) on the inner peripheral surface of the innerclutch ring 21, and this chamfered section 24 functions as a guidesurface when fitting the inner clutch ring 21 on the outer peripheralsurface of the large-diameter section 14.

[0009] On the other hand, an outer clutch ring 25 is fitted into andsecurely fastened around the middle section of the inner peripheralsurface of the follower pulley 7 a, and at least the middle section inthe axial direction of the inner peripheral surface of the outer clutchring 25 that comes in contact with rollers 26 (described later) is asimple cylindrical surface. This outer clutch ring 25 is also made ofcarburized steel plate or the like and is formed entirely into acylindrical shape by plastic process such as pressing. Provided on theopposite ends in the axial direction of the outer clutch ring 25 arering sections which form inward facing rim sections 27 a, 27 b in aflange shape. Of these rim sections 27 a, 27 b, the rim section 27 a(left rim section in FIG. 2) is formed in advance when manufacturing theouter clutch ring 25, so it has the same thickness as the cylindricalsection of the outer clutch ring 25. On the other hand, the rim section27 b (right rim section in FIG. 2) is formed after the rollers 26(described later) and clutch retainer 28 have been assembled on theinside in the radial direction of the outer clutch ring 25, so it isthin.

[0010] Also, the plurality of rollers 26, which together with the innerclutch ring 21 and outer clutch ring 25 make up the roller clutch 10,are held in place by the clutch retainer 28 which is fitted onto theinner clutch ring 21 such that it does not rotated with respect to theinner clutch ring 21, and such that the rollers 26 can roll and move alittle in the circumferential direction. This clutch retainer 28 is madefrom a synthetic resin (for example, a synthetic resin such as polyamide66, polyamide 46, polyphenylene sulfide in which glass fibers are mixedin an amount of about 20%), and as partly shown in FIG. 4, comprises apair of ring-shaped rim sections 29, and a plurality of column sections30 that connect both of these rim sections 29 to each other.

[0011] Moreover, the sections that are surrounded by the innerperipheral surfaces of the rim sections 29 and the side surfaces in thecircumferential direction of the column sections 30 are pockets 31 forsupporting the rollers 26 such that they can roll freely and displace alittle in the circumferential direction. Also, as shown in FIG. 5, thefitting protrusions 32 are formed at a plurality of locations on theinner peripheral surface of the rim sections 29, and engaged with theconcave sections 23 which are formed on the outer peripheral surface ofthe inner clutch ring 21, the clutch retainer 28 is mounted on the innerclutch ring 21 such that it is not capable of rotating relative to theinner clutch ring 21.

[0012] Also, as shown in FIG. 6, springs 33 are mounted on one of theside surfaces in the circumferential direction of the column sections 30of the clutch retainer 28. The rollers are held in the pockets 31, andthe springs 33 are mounted on each column section 30 and elasticallypress the rollers 26 in the same circumferential direction of the clutchretainer 28 (to the right or clockwise direction in FIG. 5) in thesubstantially cylindrical-shaped gap that is formed between the outerperipheral surface of the cam surface 22 and the inner peripheralsurface (cylindrical surface) in the middle section of the outer clutchring 25, toward the section of the gap where the width in the radialdirection is narrower. In the example shown in the figures, platesprings that are formed by bending spring steel plate into asubstantially triangular hook shape are used as the springs 33, howeverit is also possible to use plastic or synthetic resin springs that areintegrated with the clutch retainer 28.

[0013] Also, the opposite end surface in the axial direction of thisclutch retainer 28 come close to and face the inside surface of both rimsections 27 a, 27 b of the outer clutch ring 25, in order to prevent theclutch retainer 28 from moving in the axial direction. In addition tothis construction for preventing the clutch retainer from moving in theaxial direction, construction where a plurality of stepped sections thatare formed on the outer peripheral surface of the shaft member such asthe sleeve are engaged with part of the clutch retainer is known and hasbeen disclosed, for example, in Japanese patent publication No. Toku KaiHei 11-22753 and Japanese patent publication No. Toku Kai 2001-165201.

[0014] When there is a tendency for the follower pulley 7 a and sleeve 8to rotate relative to each other in a specified direction when using thepulley apparatus with built-in roller clutch that is constructed asdescribed above, or in other words, when there is a tendency for thefollower pulley 7 a to rotate with respect to the sleeve 8 in adirection such that the springs 33 press the rollers 26 (to the right orclockwise in FIG. 5), respectively, the rollers 26 bite into thesections of the cylindrical gap where the width in the radial directionis narrower. The follower pulley 7 a is not able to rotate relative tothe sleeve 8 (locked state). On the other hand, when the follower pulley7 a rotates relative to the sleeve 8 in the direction opposite thespecified direction, or in other words, when there is a tendency for thefollower pulley 7 a to rotate relative to the sleeve 8 in the directionopposite the direction that the springs 33 press the rollers 26 (to theleft or counterclockwise in FIG. 5), the rollers 26 move back againstthe force of the springs 33 to the section of the cylindrical gap wherethe width in the radial direction is broader, and the pulley 7 a is ableto rotate freely with respect to the sleeve 8 (overrun state).

[0015] There are two reasons for using the pulley apparatus withbuilt-in roller clutch for an alternator having the constructiondescribed above. The first reason is in order to extend the life of theendless belt. For example, in the case of using a diesel engine or adirect-injection type gasoline engine as the drive engine, changes inthe rotational angular velocity of the crankshaft become large at lowspeed such as during idling. As a result, there are small changes in therunning speed of the endless belt that extends around the drive pulley.On the other hand, the rotating shaft 3 of the alternator that isrotated and driven by this endless belt via the follower pulley does notchange so rapidly due to the inertial mass of rotating shaft 3 and therotor that is fastened to it. Also, when the follower pulley is simplyfastened to the rotating shaft, there is a tendency for rubbing to occurbetween both the endless belt and the follower pulley due to the changesin rotational angular velocity of the crankshaft. As a result, stress indiffering directions is repeatedly applied to the endless belt that rubswith this follower pulley, making it easy for slipping to occur betweenthe endless belt and the follower pulley, or causes the life of theendless belt to become shortened.

[0016] Here, by using a pulley apparatus with built-in roller clutch foran alternator as the follower pulley mentioned above, rotational poweris freely transmitted from the follower pulley to the rotating shaft 3when there is a tendency for the running speed of the endless belt to beconstant or accelerating, and in contrast, there is relative rotationbetween the follower pulley and rotating shaft 3 when there is atendency for the running speed of the endless belt to be decelerating.In other words, when there is a tendency for the running speed of theendless belt to be decelerating, the rotational angular velocity of thefollower pulley is slower than the rotational angular velocity of therotating shaft, and thus it is possible to prevent strong rubbing at thearea of contact between the endless belt and follower pulley. In thisway, direction of the stress that acts at the area of rubbing betweenthe follower pulley and endless belt is made constant, and thus it ispossible to prevent slipping from occurring between the endless belt andthe follower pulley, and prevent the life of the endless belt fromdecreasing.

[0017] The second reason is for improving the electrical generationefficiency of the alternator. The rotating shaft 3, to which thealternator rotor is fastened, is rotated and driven by the drive engineof the automobile via the endless belt and follower pulley. When a fixedtype follower pulley is used and the rotational velocity of the driveengine suddenly drops, the rotational velocity of the rotor also dropssuddenly, and thus the amount of electric current generated by thealternator also drops suddenly. On the other hand, by using a pulleyapparatus with built-in roller clutch for an alternator as the followerpulley for the alternator, the rotational velocity of the rotordecreases gradually due to the inertial force even when the rotationalvelocity of the drive engine drops suddenly, and electrical generationalso continues during that period. As a result, in comparison to usingthe fixed type follower pulley, it is possible to more effectivelyutilize the kinetic energy of the rotating shaft and rotor, and increasethe amount of electrical current generated by the alternator.

[0018] The explanation above was made for the case of installing thepulley apparatus with built-in roller clutch on the side of the followerpulley; however, similar function and results are also obtained when thepulley apparatus with built-in roller clutch having the similarconstructions as described above is installed on the end of thecrankshaft on the drive side.

[0019] In the various documentation in which the conventionalconstruction for a pulley apparatus with built-in roller clutch was beendisclosed, construction for maintaining the durability and reliabilityof the pulley apparatus with built-in roller clutch, and the method forefficiently assembling the pulley apparatus with built-in roller clutchwere not specifically disclosed.

[0020] Taking the above problems into consideration, it is an object ofthis invention to provide a pulley apparatus with built-in roller clutchthat is capable of maintaining sufficient durability and reliability,and provide a method for assembling the pulley apparatus with built-inroller clutch easily.

DISCLOSURE OF THE INVENTION

[0021] The pulley apparatus with built-in roller clutch of thisinvention in a feature comprises: a pulley, a rotating shaft that is ashaft member, a roller clutch, a first ball bearing and a second ballbearing.

[0022] Of these, the pulley has a substantially cylindrical shape suchthat an endless belt can freely run around its outer peripheral surface.

[0023] Also, the rotating shaft is located on the inner-diameter side ofthe pulley such that it is concentric with the pulley.

[0024] Moreover, the roller clutch is installed between the innerperipheral section of the middle section in the axial direction of thepulley and the outer peripheral section of the middle section in theaxial direction of the rotating shaft, and it transmits rotational forceonly in one direction between the pulley and the rotating shaft, or inother words, it is locked in one direction of rotation and unlocked inthe other direction.

[0025] The roller clutch as mentioned above comprises: an outer-diametersection that corresponds to the like of outer clutch ring, aninner-diameter section that corresponds to the like of inner clutchring, a retainer, a plurality of rollers, a plurality of springs, afall-out-prevention means, and a second engagement section and firstengagement section, which correspond to the fitting section and fittedsection.

[0026] Of these, the like of outer clutch ring is formed around theinner peripheral surface of the middle section in the axial direction ofthe pulley.

[0027] Also, the like of inner clutch ring is formed around the outerperipheral surface of the middle section in the axial direction of therotating shaft, and the outer peripheral surface is uneven in thecircumferential direction to form a cam surface that corresponds to thecam section.

[0028] Also, the retainer is located between the outer peripheralsurface of the like of inner clutch ring and the inner peripheralsurface of the like of outer clutch ring, and has a plurality ofpockets.

[0029] Moreover, the rollers are held inside the pockets of the retainersuch that they can roll freely and move in circumferential direction ofthe retainer.

[0030] The springs are located between the rollers and the retainer, orin other words, they are engaged with the retainer to press the rollersin the same direction or circumferential direction of the retainer.

[0031] The fall-out-prevention means is located in part of the retainer,and prevents the rollers inside the pockets from falling out of thepockets into the inside in the radial direction of the retainer.

[0032] With respect to the fitting section and fitted section, thefitting section is formed on the inner peripheral surface of theretainer, and the fitting section is engaged with the fitted sectionthat is formed on the like of inner clutch ring, such that it ispossible to prevent the retainer from rotating with respect to the likeof inner clutch ring.

[0033] Also, the first ball bearing is located between the innerperipheral section on one end in the axial direction of the pulley andthe outer peripheral section on one end in the axial direction of therotating shaft, and it supports radial loads and axial loads that areapplied between the pulley and rotating shaft. The outer-diametersection of this first ball bearing is located on the inner peripheralsection on one end in the axial direction of the pulley to have a firstouter-ring raceway on the inner peripheral surface of the outer-diametersection. Also, the inner-diameter section of the first ball bearing islocated on the outer peripheral section on one end in the axialdirection of the rotating shaft to have a first inner-ring raceway onthe outer peripheral surface of the inner-diameter section. Moreover,there is a plurality of first balls that roll freely between the firstinner-ring raceway and the first outer-ring raceway.

[0034] The second ball bearing is located between the inner peripheralsurface on the other end in the axial direction of the pulley and theouter peripheral surface on the other end in the axial direction of therotating shaft, and it supports radial loads and axial loads that areapplied between the pulley and rotating shaft. This second ball bearinghas a second outer-ring raceway that is formed around the innerperipheral surface of the outer bearing race that is fitted into theinner peripheral surface of the other end in the axial direction of thepulley, a second inner-ring raceway that is formed around the outerperipheral surface of the inner bearing race that is fitted onto theouter peripheral surface of the other end in the axial direction of therotating shaft, and a plurality of second balls that roll freely betweenthe second inner-ring raceway and the second outer-ring raceway.Moreover, the rotating shaft and inner bearing race form a shaft unit orrotating-shaft unit.

[0035] Also, this rotating-shaft unit has a plurality of step sectionsthat are formed around its outer peripheral surface. Two of these stepsections are engaged with part of the retainer, so that it is possibleto suppress movement in the axial direction of the retainer.

[0036] Furthermore, a chamfered section is formed on at least one of theend sections in the axial direction of the rollers for the roller clutchand the outer peripheral edge on one end surface in the axial directionof the like of inner clutch ring. The chamfered section becomes aguiding surface when bringing the like of inner clutch ring and therollers together in the axial direction in order that the rollers can beplaced around the like of inner clutch ring, while at the same timemoving the rollers in the circumferential direction by the cam surfaceagainst the force of the springs. Incidentally, when the chamferedsection is formed on the end in the axial direction, of the cam surfacethe “cam surface” includes this chamfered section.

[0037] The total amount of chamfering of the chamfered section (width inthe radial direction) is larger than the dimension of overlap of therollers and the like of inner clutch ring as seen from the axialdirection. In other words, when the rollers and the like of inner clutchring are seen from the axial direction with the retainer and the like ofinner clutch ring placed such that they are concentric, and with aspecified phase provided in the circumferential direction (part of therolling contact surface of the rollers that are held in the retainercomes in contact with the inner peripheral surface of the like of outerclutch ring, and the rollers are pressed in the circumferentialdirection by the springs), the total amount of chamfering on thechamfered section, which is formed on at least one of the ends in theaxial direction of the rollers and the outer peripheral edge on one endsurface in the axial direction of the like of inner clutch ring, isgreater than the dimension of overlapping between the rollers and thelike of inner clutch ring.

[0038] Furthermore, in the assembly method for assembling the pulleyapparatus with built-in roller clutch of this invention, in order toassemble the pulley apparatus with built-in roller clutch as describedabove, first, with the rollers held inside the pockets that are formedin the retainer of the roller clutch and pressed to one side in thecircumferential direction of the pockets by the springs, the rollers andretainer are placed on the inner-diameter side of the like of outerclutch ring to form an assembly.

[0039] Then, the fitting section of the retainer is engaged with thefitted section of the like of inner clutch ring between the side of oneend in the axial direction of the retainer and the side of one end inthe axial direction of the like of inner clutch ring of the rollerclutch, relative rotation between the like of inner clutch ring and theretainer is prevented.

[0040] Next, in order to assemble the like of inner clutch ring of theroller clutch on the inner-diameter side of the springs and the rollersthat are held in the retainer, the end of the like of inner clutch ringis pressed toward the inner-diameter side of the rollers using as aguide the chamfered section that is formed on at least one of the endsin the axial direction of the rollers and the outer peripheral edge onone end surface in the axial direction of the like of inner clutch ring,or in other words, while using the chamfered section to press the likeof inner clutch ring under the rollers held by the retainer, or towardthe inner-diameter side of the rollers, the rollers are movedsimultaneously by the cam surface, which is formed on the outerperipheral surface of the like of inner clutch ring, in thecircumferential direction against the spring force, the rollers aremoved to a specified position in the circumferential direction betweenthe inner peripheral surface of the like of outer clutch ring and theouter peripheral surface of the like of inner clutch ring. Thus theroller clutch as mentioned above is formed.

[0041] After the roller clutch has been assembled between the innerperipheral surface of the middle section in the axial direction of thepulley and the outer peripheral surface of the middle section in theaxial direction of the rotating shaft, the second ball bearing isassembled between the inner peripheral surface on the other end in theaxial direction of the pulley and the outer peripheral surface on theother end in the axial direction of the rotating shaft.

[0042] The first ball bearing is assembled between the inner peripheralsection on one end in the axial direction of the pulley and the outerperipheral section on one end in the axial direction of the rotatingshaft before assembling the second ball bearing. It does not matterwhether assembly of the first ball bearing is before or after assemblyof the roller clutch.

[0043] The work of securing the second ball bearing, which is assembledbetween the inner peripheral surface on the other end in the axialdirection of the pulley and the outer peripheral surface on the otherend in the axial direction of the rotating shaft, can be performed byany one of the following methods: pressure fitting, crimping, welding oradhesive.

[0044] In the case of another assembly method for assembling the pulleyapparatus with built-in roller clutch in another feature of thisinvention, a jig, whose outer shape is nearly the same as that of thelike of inner clutch ring and which has a chamfered section on the sideof the jig that is inserted inside the inner-diameter side of therollers, is used to insert the like of inner clutch ring whilecompressing all of the springs simultaneously.

[0045] The pulley apparatus with built-in roller clutch of thisinvention and the method of assembling it make it possible to maintainsuitable durability and reliability, as well as simplify assembly work.

[0046] The function and effect of being possible to maintain suitabledurability and reliability is obtained by the engagement between aplurality of stepped sections that are formed around the outerperipheral surface of the rotating-shaft unit with part of the retainerin order to suppress movement in the axial direction of the retainer. Inother words, the retainer is prevented from moving in the axialdirection by the engagement between the stepped sections with part ofthe retainer, so the end surfaces in the axial direction of the retainerdoes not come in contact with the parts that rotate together with thepulley, such as part of the outer clutch ring. The retainer is installedsuch that it does not rotate with respect to the like of inner clutchring that is fastened to the outer peripheral surface of therotating-shaft. Accordingly, the pulley and retainer rotate relative toeach other when the roller clutch is in overrun (when the connection isbroken). Therefore, when the end surface in the axial direction of theretainer comes in contact with the parts that rotate together with thepulley such as part of the outer clutch ring, the temperature of theroller clutch rises due to the friction heat caused by rubbing at thearea of contact during overrun. Also, as this temperature rise becomesexcessive, the grease inside the roller clutch degrades and theanti-seizure capability is lost, so it becomes difficult to obtainadequate durability.

[0047] On the other hand, in the case of the pulley apparatus withbuilt-in roller clutch of this invention, there is no relative rotationof the retainer to the rotating-shaft unit even during overrun, andmovement in the axial direction of the retainer in the axial directionis suppressed between the retainer and the rotating-shaft unit, sostrong rubbing between the retainer and opposing surfaces during overrunis prevented, and thus it is possible to suppress the friction heat thatoccurs during overrun, and to prevent degradation of the grease, so thatdurability is secured. Moreover, since it is possible to effectivelyprevent movement in the axial direction of the retainer and the like ofinner clutch ring, it is possible to prevent the rolling contactsurfaces of the rollers that are held by the retainer from separating inthe axial direction away from the cam surface that is formed on theouter peripheral surface of the like of inner clutch ring. Therefore, itis possible to prevent an edge load from being applied to any part ofthe rolling contact surfaces as part of the rolling contact surfaces ofthe rollers come in contact with the end edge in the axial direction ofthe cam surface, and thus it is possible to prevent a decrease infatigue life of these rolling contact surfaces and to improve thedurability as well.

[0048] Also, simplification of the assembly work is made possible byforming the fall-out-prevention means and chamfering.

[0049] First, of these, the fall-out-prevention mean prevents therollers that are held in the pockets of the retainer from falling insidein the radial direction of the retainer, so it becomes easy to performthe work of inserting the like of inner clutch ring, with the camsurface formed around its outer peripheral surface, into theinner-diameter side of the retainer and rollers that are assembledbeforehand into the like of outer clutch ring. In other words, whenthere is no fall-out-prevention means, all or part of the rollers thatare held in the pockets protrude or fall into the inner-diameter side ofthe retainer, and makes it difficult to push the like of inner clutchring into the inner-diameter side of the retainer. On the other hand, inthe case of this invention, there is a fall-out-prevention means thatprevents the rollers from protruding or falling on the inner-diameterside of the retainer when pushing the like of inner clutch ring, makingit possible to easily perform the work of pushing. In other words, theretainer for the roller clutch of this invention has two positioncontrol functions in one retainer; preventing the rollers fromprotruding too much or falling into the inner-diameter side of theretainer during assembly, and preventing the retainer itself from movingin the axial direction during use. From these two functions it ispossible to simplify the assembly work and to maintain durability andreliability.

[0050] Also, the work of pushing the like of inner clutch ring in can beperformed even easier by forming a chamfered section on at least one ofthe ends in the axial direction of the rollers and the outer peripheraledge of one end surface in the axial direction of the inner clutch ring.In other words, this chamfered section becomes a guiding surface whenbinging the like of inner clutch ring closer to the rollers in the axialdirection in order to place the rollers around the like of inner clutchring, so the work of pushing the end section of the like of inner clutchring into the inner-diameter side of the rollers can be performedeasily. That is, the fitting section that is formed on the retainer isengaged with the fitted section that is formed on the like of innerclutch ring in order to restrict the phase in the circumferentialdirection of the like of inner clutch ring and the retainer and preventrelative rotation between them, and then the like of inner clutch ringis pushed into the inner-diameter side of the rollers. Consequently, thechamfered section allows the like of inner clutch ring to be insertedinto the inner-diameter side of the rollers.

[0051] Also, when pushing the like of inner clutch ring into theinner-diameter side of the rollers in this way, the cam surface that isformed on the outer peripheral surface of the like of inner clutch ringcauses the rollers to simultaneously move in the circumferentialdirection against the force of the springs. Furthermore, these rollersare moved into a specified place between the inner peripheral surface ofthe like of outer clutch ring and the outer peripheral surface of thelike of inner clutch ring (for example, at a portion closer to the outerdiameter of the concave section of the cam surface where the portionsimultaneously comes in contact with the inner peripheral surface of thelike of outer clutch ring and the outer peripheral surface of the likeof inner clutch ring), to form the roller clutch. Moving the rollersagainst the force of the springs to their specified location in this wayis performed simultaneously for all of the rollers by the work ofpushing the like of inner clutch ring into the inner-diameter side ofthe rollers, and thus making it possible to easily assemble the rollerclutch. Moving the rollers simultaneously by the cam surface in thecircumferential direction against the force of the springs in this waymeans moving the rollers to specified locations in the circumferentialdirection between the inner peripheral surface of the like of outerclutch ring and the outer peripheral surface of the like of inner clutchring, as described above. It is by moving the rollers to specifiedlocations between both of these surfaces in this way that it becomespossible to freely transmit rotation force between the like of outerclutch ring and the like of inner clutch ring. Incidentally, when thereis a chamfered section formed on the ends in the axial direction of thecam surface, the “cam surface” includes that chamfered section.

[0052] In short, in the case of this invention, with thefall-out-prevention means, it is possible to prevent the diameter of theinscribed circle of the rollers from becoming too small when the rollersare assembled on the inner-diameter side of the like of outer clutchring, as well as it is possible to prevent the rollers from protrudingtoo far or falling into the inner-diameter side of the retainer, and achamfered section is formed, so the inclined surfaces of the pluralityof concave sections of the cam surface simultaneously move the rollersin the circumferential direction of the like of inner clutch ring whenthe like of inner clutch ring is pushed into the inner-diameter sectionof the rollers, resulting in that the rollers are moved to theirspecified locations. Therefore, there is no need to perform troublesomework such as independently compressing each individual spring whenassembling the rollers and springs, and thus it is possible to moreeasily and efficiently assemble the pulley apparatus with built-inroller clutch.

[0053] To repeat, in the case of this invention, with thefall-out-prevention means that is formed on the retainer of the rollerclutch, movement of the rollers toward the inner-diameter side of theretainer is suppressed, and it becomes easier to insert the like ofinner clutch ring into the inner-diameter section of the retainer. Also,by using the chamfered section to insert the like of inner clutch ringinto the inner-diameter side of the rollers, the springs aresimultaneously compressed, and the rollers are simultaneously moved totheir specified positions. Therefore, it becomes easy to perform thework of moving the rollers to their specified positions against theforce of the springs, which up until now was troublesome because therewas a plurality of rollers and springs. In other words, in regards toassembling the retainer, rollers, springs and the like of inner clutchring, the like of inner clutch ring can easily be brought in contactwith the rollers, and after they have been brought in contact, the workof simultaneously compressing the springs and moving the rollers totheir specified positions can also be performed easily.

BRIEF DESCRIPTION OF THE DRAWINGS

[0054]FIG. 1 is a cross sectional view to show an example of theconventional alternator.

[0055]FIG. 2 is a cross sectional view of a half of an example of theconventional structure.

[0056]FIG. 3 is a partial perspective view of an inner clutch ring.

[0057]FIG. 4 is a partial perspective view of a clutch retainer.

[0058]FIG. 5 is a partial side elevational view of the inner clutch ringand the clutch retainer with the other parts away.

[0059]FIG. 6 is a perspective view of an example of the spring mountedto a clutch retainer.

[0060]FIG. 7 is a cross sectional view of a half of a first example ofthe embodiment of the pulley apparatus with built-in roller clutchaccording to the present invention.

[0061]FIG. 8 is a cross sectional view to show an example of thefall-out-prevention means to prevent the rollers from coming offradially inwards from the pockets in the clutch retainer.

[0062]FIG. 9 is a partial, enlarged perspective view to show a chamferedportion on the outer peripheral edge at one end of the inner clutchring.

[0063]FIG. 10 is a cross sectional view to show an engagement state of achamfered portion on the outer peripheral edge at one end of the innerclutch ring and rollers.

[0064]FIG. 11 is a view, seen from an side in FIG. 7, of the locationrelation between the inner clutch ring and rollers before the innerclutch ring is pushed on the inner-diameter side of the rollers.

[0065]FIG. 12 show schematic cross sectional views to show an example ofthe assembly process of the pulley apparatus with built-in roller clutchaccording to a first example of the embodiment.

[0066]FIG. 13 is a cross sectional view of a half of a second example ofthe embodiment of the pulley apparatus with built-in roller clutch ofthe present invention.

[0067]FIG. 14 shows schematic cross sectional views to show an exampleof the assembling process of the puller apparatus with built-in rollerclutch according to the second example of the present embodiment.

[0068]FIG. 15 is a cross sectional view of a half of a third example ofthe embodiment of the pulley apparatus with built-in roller clutch ofthe present invention.

[0069]FIG. 16 is a cross sectional view of a half of a fourth example ofthe embodiment of the pulley apparatus with built-in roller clutch ofthe present invention.

[0070]FIG. 17 is a cross sectional view of a half of a fifth example ofthe embodiment of the pulley apparatus with built-in roller clutch ofthe present invention.

[0071]FIG. 18 is a cross sectional view of a half of a sixth example ofthe embodiment of the pulley apparatus with built-in roller clutch ofthe present invention.

[0072]FIG. 19 shows brief cross sectional views of another twelveexamples of the structure of a portion to suppress axial displacement ofthe clutch retainer.

[0073]FIG. 20 shows brief cross sectional views of another thirteenexamples.

[0074]FIG. 21 shows substantial cross sectional views of another sixexamples.

[0075]FIG. 22 shows substantial cross sectional views of another twoexamples.

[0076]FIG. 23 is a brief cross sectional view of a second example of thefall-out-prevention means to prevent the rollers from coming offradially inwards from the pockets of the clutch retainer.

[0077]FIG. 24 is a schematic cross sectional view of a third example ofthe fall-out-prevention means.

[0078]FIG. 25 shows a fourth example of the fall-out-prevention means,wherein (A) is a schematic cross sectional view, and (B) is a view seenfrom the lower side of (A) with rollers omitted.

[0079]FIG. 26 shows a fifth example of the fall-out-prevention means,wherein (A) is a schematic cross sectional view, and (B) is a crosssectional view taken along the line E-E in (A).

[0080]FIG. 27 is a schematic cross sectional view to show a sixthexample of the fall-out-prevention means.

[0081]FIG. 28 is a schematic cross sectional view to show a seventhexample of the fall-out-prevention means.

[0082]FIG. 29 is a schematic cross sectional view to show an eighthexample of the fall-out-prevention means.

[0083]FIG. 30 is a schematic cross sectional view of a jig for use inworking an embodiment of the present invention.

THE BEST EMBODIMENTS TO WORK THE INVENTION

[0084] FIGS. 7 to 11 show a first example of the embodiment of theinvention. A feature of this invention is that by preventing rubbingbetween the clutch retainer 28 a and the parts that rotate together withthe follower pulley 7 a during overrun, it is possible to suppress arise in temperature due to friction heat and to improve durability, aswell as this invention makes it possible to simplify the work ofassembling the roller clutch 10 a on the inner-diameter side of thefollower pulley 7 a. The construction and function of the other partsare substantially the same as that of the prior art construction shownin FIGS. 2 to 6, so the like code numbers will be used for like partsand any redundant explanation will be omitted. The following explanationwill center on the features of this invention and the parts that differfrom the prior construction.

[0085] First, the construction of the part, which suppressesdisplacement in the axial direction of the clutch retainer 28 a in orderto suppress the rise in temperature, will be explained. This clutchretainer 28 a is made of synthetic resin having sufficient elasticityand is formed by injection molding such that on one end in the axialdirection (right end in FIG. 7) there is an inward facing flange-shapedfastening rim section 34 that is formed all the way around orintermittently around in the circumferential direction. On the other endin the axial direction of the clutch retainer 28 a, there is one toseveral fastening protrusions 35 formed intermittently around in thecircumferential direction to protrude inward in the radial direction.The inner peripheral surface of this fastening protrusions 35 isinclined outward in the radial direction towards the tips, and act asinclined guide surfaces 36. On the other hand, an inner clutch ring 21of the roller clutch 10 a is securely fastened around the outerperipheral surface in the middle section of the rotating member orsleeve 8 through interference fit, and a plurality of stepped sectionsare formed on the opposite end surfaces in the axial direction of theinner clutch ring 21. Also, the opposite end surfaces in the axialdirection of the inner clutch ring 21 are engaged with the matingsurfaces of the fastening rim section 34 and the fastening protrusions35, so that movement in the axial direction of the clutch retainer 28 ais suppressed.

[0086] Next, FIG. 8 will be used to explain the fall-out-preventionmeans of preventing the rollers 26 from falling out of the pockets 31formed in the clutch retainer 28 a into the inner-diameter side of theclutch retainer 28 a. As shown in FIG. 8, the rollers 26 are held in thepockets 31 that are formed in the clutch retainer 28 a such that theycan roll freely and move in the circumferential direction of the clutchretainer 28 a. However, with respect to the openings of the pockets 31,the width W₃₁ in the circumferential direction of the opening on theinner-diameter side of the clutch retainer 28 a is less than thediameter D₂₆ of the rollers 26 (W₃₁<D₂₆). Therefore, the rollers 26cannot pass through the openings on the inner-diameter side of theclutch retainer 28 a, and thus the rollers 26 do not fall into theinner-diameter side of the clutch retainer 28 a.

[0087] Next, FIGS. 9 to 11 will be used to explain about the chamferedsections that are formed on the outer peripheral edge on one end in theaxial direction of the inner clutch ring 21 and the ends in the axialdirection of the rollers so that the inner clutch ring 21 can beinserted into the inner-diameter side of the rollers 26. First, as shownin FIG. 9, a chamfered section 38 is formed all the way around the outerperipheral edge of one end surface in the axial direction of the innerclutch ring 21 such that it connects the cam surface 22 that is formedon the outer peripheral surface of the inner clutch ring 21 to the endsurface 37 in the axial direction of the inner clutch ring 21. Thischamfered section 38 is inclined inward in the radial direction from thecam surface 22 to the end surface 37.

[0088] On the other hand, as shown in FIG. 10, there is a chamferedconvex section 39, having a quarter arch-shaped or partialconical-shaped cross section, formed on the ends in the axial directionof the rollers 26.

[0089] These chamfered sections 38, 39 act as guiding surfaces whenbringing the inner clutch ring 21 together with the rollers 26 closer toeach other in an axial direction in order to place the rollers 26 aroundthe inner clutch ring 21, or in other words, to place the inner clutchring 21 on the inner-diameter side of the rollers 26, so that therollers 26 are moved in the circumferential direction against the forceof the springs 33 by the cam surface 22. In other words, when pushingthe inner clutch ring 21 into the inner-diameter side of the rollers 26in order to place the inner clutch ring 21 on the inner-diameter side ofthe rollers 26, due to the engagement between the chamfered sections 38,39, it is possible to push the inner roller-clutch ring 21 into theinner-diameter side of the rollers 26 with no interference between theouter peripheral edge on the ends in the axial direction of the rollers26 and the outer peripheral edge on the ends in the axial direction ofthe inner roller-clutch ring 21.

[0090] In order to accomplish this, the amount of chamfering of thechamfered sections 38, 39, that is, the total width W₃₈ and W₃₉ in theradial direction of these chamfered sections 38, 39 is regulated asdescribed below by the relationship with the rollers 26 and the innerclutch ring 21. In other words, in the initial step of pushing the innerclutch ring 21, the end in the axial direction of the inner clutch ring21 is inserted into the end in the axial direction of the clutchretainer 28 a, in order that the concave sections 23 of the cam surface22 on the outer peripheral surface of the inner roller-clutch ring 21are engaged with the fitting protrusions 32 that are formed on the innerperipheral surface of the clutch retainer 28 a, as shown in FIG. 5. Inthis state, the phase in the circumferential direction of the innerclutch ring 21 and the clutch retainer 28 a is regulated (relativerotation of these parts 21, 28 a is not possible). However, in thisinitial step, the rollers 26 and the inner clutch ring 21 are stillseparated in the axial direction. Also, these rollers 26 are pressed bythe springs 33, with respect to the phase in the circumferentialdirection, to be moved to the section where the depth of the concavesections 23 becomes shallow (sections where the gap between the outerperipheral surface of the inner clutch ring 21 and the inner peripheralsurface of the outer clutch ring 25 is narrower).

[0091] In this state, as shown in FIG. 11, part of these rollers 26 arelocated further inward in the radial direction than the part on theouter peripheral surface of the inner clutch ring 21 which matches therollers 26 in the phase in the circumferential direction, even when thespring force of the springs that presses the rollers 26 has a componentforce outward in the radial direction of the clutch retainer 28 a sothat the rollers 26 are brought into contact with the inner peripheralsurface of the inner clutch ring 25. In other words, part of the innerclutch ring 21 overlaps part of the rollers 26 in the axial direction.In this state, when the amount that these parts 26, 21 overlap is takento be δ, the total width W₃₈ and W₃₉ in the radial direction of thechamfered sections 38, 39 is greater than the amount of overlap δ(W₃₈+W₃₉>δ). As long as this relationship (W₃₈+W₃₉>δ) is satisfied,either one of these widths W₃₈ and W₃₉ can be ‘0’. By regulating thesize of the chamfered sections 38, 39 in this way, the inner clutch ring21 is pushed into the inner-diameter side of the clutch retainer 28 aand rollers 26 that are located beforehand on the inner peripheralsurface of the outer clutch ring 25.

[0092] The work of assembling the pulley apparatus with built-in rollerclutch of this invention, which is constructed with the componentsdescribed above, is performed, for example, as shown in FIG. 12. First,as shown in FIG. 12(A), the springs 33 (see FIGS. 6 and 11) are mountedin the clutch retainer 28 a, and the rollers 26 are held in the pockets31 that are formed in the clutch retainer 28 a. In this state, therollers 26 are pushed to one end in the circumferential direction of thepockets 31 by the springs 33. Then, as shown in FIG. 12(B), the rollers26, springs 33 and clutch retainer 28 a are assembled on theinner-diameter side of the outer clutch ring 25. In this state, therollers 26 are prevented from falling into the inner-diameter side ofthe clutch retainer 28 a by the fall-out-prevention means as shown inFIG. 8.

[0093] Then, as shown in FIG. 12(C), the inner clutch ring 21 isassembled into the inner-diameter side of the rollers 26. Whenassembling this inner clutch ring 21, first, the fitting section or thefitting protrusions 32 is engaged with the concave section 23 on thefitted section or the cam surface 22 between one end in the axialdirection of the clutch retainer 28 a and one end in the axial directionof the inner clutch ring 21 as shown in FIG. 5, so that the inner clutchring 21 is prevented from rotating relative to the clutch retainer 28 a.In other words, the phase in the circumferential direction of theseparts 21, 28 a is to be in the normal state (assembled state). In thisstate, one end in the axial direction of the inner clutch ring 21 is notyet inserted into the inner-diameter side of the end section of therollers 26.

[0094] With the one end in the axial direction of the clutch retainer 28a inserted into the one end section in the axial direction of the innerclutch ring 21 and with the phase in the circumferential direction ofboth of these parts 28 a, 21 regulated in this way, the inner clutchring 21 is pushed into the inner-diameter side of the springs 33 and therollers 26 in order to assemble the inner clutch ring 21 in theinner-diameter side of the rollers 26, which are held by the clutchretainer 28 a. When pushing the inner clutch ring 21, the chamferedsections 38, 39 that are formed on the ends in the axial direction ofthe inner clutch ring 21 and rollers 26 function as guide surfaces.Therefore, the work of pushing the inner clutch ring 21 into theinner-diameter side of the rollers 26 is not particularly troublesomeand can be performed smoothly.

[0095] At the instant that the work of pushing in the inner clutch ring21 begins, the phase in the circumferential direction of the innerclutch ring 21 and the rollers 26 is as shown in FIG. 11. As can beclearly seen from FIG. 11, with the phase of the rollers 26 in thecircumferential direction of the inner clutch ring 21 as is, it is notpossible to push in the inner clutch ring 21. The reason for this isthat for the portion that coincides with the rollers 26 with referenceto the phase in the circumferential direction of the inner clutch ring21, the distance L between the cam surface 22 that is formed on theouter peripheral surface of the inner clutch ring 21 and the innerperipheral surface of the outer clutch ring 25 is less than the diameterD₂₆ of the rollers 26 (L<D₂₆). However, when the inner clutch ring 21 ispushed further into the inner-diameter side of the roller 26, the camsurface 22 that is formed on the outer peripheral surface of the innerclutch ring 21 moves the rollers 26 in the circumferential directionagainst the force of the springs 33. This cam surface 22 includes thechamfered section 38 that is formed on the end in the axial direction ofthe clutch inner ring 21.

[0096] In other words, at the same time that the end section in theaxial direction of the inner clutch ring 21 is pushed into theinner-diameter side of the rollers 26 due to the engagement of thechamfered sections 38, 39, the inclined surfaces of the concave sections23 of the cam surface 22 press the rollers 26 in directionsperpendicular to these inclined surfaces. Also, of the force in thisperpendicular direction, the component force in the circumferentialdirection of the inner clutch ring 21 moves the rollers 26 against theforce of the springs 33, as shown by the dotted line in FIG. 11, to aspecified position in the circumferential direction between the innerperipheral surface of the outer clutch ring 25 and the outer peripheralsurface of the inner clutch ring 21, or in other words, to the placewhere the distance between both of these peripheral surfaces coincideswith the diameter D₂₆ of the rollers 26. In this state, assembly of theroller clutch 10 a itself is complete. Pushing the inner clutch ring 21into the inner-diameter side of the clutch retainer 28 a is performedfrom the side of the fastening protrusion 35 (see FIG. 7) that areformed on the other end in the axial direction of the clutch retainer 28a. When pushing the inner clutch ring 21 in, this fastening protrusion35 is elastically deformed outward in the radial direction.

[0097] As shown in FIG. 12(D), the roller clutch 10 a that is assembledin this way is assembled on the inner peripheral surface of the middlesection in the axial direction of the follower pulley 7 a by securelyattaching the outer clutch ring 25 into the follower pulley 7 a throughinterference fit. Then, as shown in FIG. 12(E), by attaching the innerclutch ring 21 onto the sleeve 8 through interference fit, the rollerclutch 10 a is assembled on the outer peripheral surface of the middlesection in the axial direction of the sleeve 8. In this state, theroller clutch 10 a is assembled between the inner peripheral surface ofthe middle section of the follower pulley 7 a and the outer peripheralsurface of the middle section of the sleeve 8.

[0098] Finally, as shown in FIG. 12(F), the first and second ballbearings 9 are assembled on the opposite sides in the axial direction ofthe roller clutch 10 a between the inner peripheral surface of thefollower pulley 7 a and the outer peripheral surface of the sleeve 8 atthe opposite ends in the axial direction thereof. In this state, thepulley apparatus with built-in roller clutch is complete as shown inFIG. 7.

[0099] A feature of the assembly method of this invention is in theprocess of assembling the inner clutch ring 21 on the inner-diameterside of the clutch retainer 28 a, the rollers 26 and springs 33 whichhave already been assembled on the inner-diameter side of the outerclutch ring 25, in order to assemble the roller clutch 10 a. The otherprocesses can be changed and performed as suitable and not limited tothe order shown in FIG. 12. For example, it is possible to assemble theclutch retainer 28 a, rollers 26, springs 33 and inner clutch ring 21 onthe inner-diameter side of the outer clutch ring 25 that has alreadybeen fitted and attached into the inner peripheral surface in the middlesection in the axial direction of the follower pulley 7 a. Furthermore,with respect to the pair of ball bearings 9, one of the ball bearings 9can be assembled between the inner peripheral surface of the followerpulley 7 a and the outer peripheral surface of the sleeve 8 beforeassembling the roller clutch 10 a.

[0100] Next, FIG. 13 shows a second example of the embodiment of theinvention. In this example, the like of outer clutch ring 40 of theroller clutch 10 a is integrated with the follower pulley 7 a, and thelike of inner clutch ring 41 is integrated with the sleeve 8,respectively as a single body.

[0101] When assembling this embodiment, the rollers 26 and springs areassembled in the clutch retainer 28 a as shown in FIG. 14(A), and thenthese parts are assembled on the inner-diameter side of the like ofouter clutch ring 40 as shown in FIG. 14(B). Next, as shown in FIG.14(C), the like of inner clutch ring 41 is assembled on theinner-diameter side of the rollers 26 to form the roller clutch 10 a,after which the pair of ball bearings 9, 9 are assembled on both side ofthe roller clutch 10 a as shown in FIG. 14(D).

[0102] The construction and function of the other parts aresubstantially the same as in the first example described above, so anyredundant figures or explanations are omitted.

[0103] Next, FIGS. 15 to 18 show third to sixth examples of theembodiments of the invention.

[0104] First, in the case of the third example shown in FIG. 15, theouter clutch ring 25 is attached on the inner peripheral surface of themiddle section in the axial direction of the follower pulley 7 a, andthe like of inner clutch ring 41 is integrated with and formed on theouter peripheral surface of the middle section in the axial direction ofthe sleeve 8.

[0105] Next, in the case of the fourth example shown in FIG. 16, theinner clutch ring 21 is fitted and attached onto the outer peripheralsurface of the middle section in the axial direction of the sleeve 8,and the like of outer clutch ring 40 is integrated with and formedaround the inner peripheral surface of the middle section in the axialdirection of the follower pulley 7 a.

[0106] Next, in the case of the fifth example shown in FIG. 17, the likeof the inner race of the ball bearing 9 a, that corresponds to the firstball bearing, is integrated with the sleeve 8, and similarly, the likeof the outer race is integrated with the follower pulley 7 a.

[0107] Furthermore, in the case of the sixth example shown in FIG. 18,the like of the outer clutch ring 40 of the roller clutch 10 a isintegrated with the follower pulley 7 a, and the like of the innerclutch ring 41 is integrated with the sleeve 8, and the like of theinner race of the ball bearing 9 a, that corresponds to the first ballbearing, is integrated with the sleeve 8, and similarly the like of theouter race is integrated with the follower pulley 7 a.

[0108] The construction and function of the other parts of the third tosixth examples are substantially the same as in the first and secondexamples described above so any redundant figures or explanations areomitted.

[0109] Next, FIGS. 19 to 21 are used to explain a different example ofthe construction of the section that suppresses displacement in theaxial direction of the clutch retainer 28 a by engaging part of theclutch retainer 28 a with a plurality of step sections 53 that areformed around the outer peripheral surface of the rotating-shaft unit 52wherein the inner race 18 of at least one of the ball bearings 9 (9 a)of the rotating-shaft unit 52 is fitted onto or integrally formed on therotating-shaft member 8. The step sections 53 that are formed around theouter peripheral surface of the rotating-shaft unit 52, include theintegrated step sections 53 that protrude from the outer peripheralsurface of the rotating-shaft unit 52 (for example as shown in FIG.19(A)), the side surfaces 53 of the concave grooves 55 that are formedon the outer peripheral surface of the rotating-shaft member 8 (forexample as shown in FIG. 19(C)), as well as the end surfaces 53 in theaxial direction of the inner clutch ring 21 (the like 41 of inner clutchring) that is fitted and fastened onto the rotating-shaft member 8 andthe inner bearing race 18 of the ball bearing 9 (9 a) (for example asshown in FIG. 19(B)).

[0110] Of the construction for suppressing movement in the axialdirection of the clutch retainer 28 a using this kind of step section53, FIGS. 19(A) to 19(L) show a fastening section 54 that is bent inwardin the radial direction from one end in the axial direction of theclutch retainer 28 a such that it is located between a pair of stepsections 53; FIG. 20(A) to FIG. 20(M) show both ends in the axialdirection of the clutch retainer 28 a (including the fastening sections54 that are bent inward in the radial direction from these ends) suchthat they are located between a pair of step sections 53; FIG. 21(A) toFIG. 21(F) show a pair of step sections 53 that are held between a pairof fastening sections 54 that are bent inward in the radial directionfrom both ends in the axial direction of the clutch retainer 28 a; andFIG. 22(A) and FIG. 22(B) show a step section 53 that are held between apair of fastening sections 54 that protrude inward in the radialdirection and are formed on one end in the axial direction of the clutchretainer 28 a.

[0111] Next, FIG. 23 to FIG. 29 are used to explain a different exampleof the fall-out-prevention means of preventing the rollers 26 that areheld in the pockets 31 of the clutch retainer 28 a from falling from thepockets 31 into the inner-diameter side of the clutch retainer 28 a.

[0112] First, FIG. 23 shows a spring 33 that presses the roller 26against the inclined surface 42 of the inner surface of the pocket 31and applies an elestic force on the roller 26 outward in the radialdirection of the clutch retainer 28 a.

[0113] Also, FIG. 24 shows protruding tabs 43 that are formed on theopening of the inner-diameter side of the pocket 31 such that thedistance between the tips of these tabs 43, 43 is less than the diameterof the roller 26.

[0114] Also, FIG. 25 shows a filament type of wire material 44 that runsacross the pocket 31 in the axial direction near the inner diameter sideof the clutch retainer 28 a, and the distance between this wire material44 and the mating surface of the pocket 31 is less than the diameter ofthe roller 26.

[0115]FIG. 26 shows mounting a wire ring 45 on the inner peripheralsurface of the opposite ends of the clutch retainer 28 a, and alsoforming a protrusion 46 on the opposite ends of the roller 26, such thatdisplacement of the roller 26 in the radial direction of the clutchretainer 28 a is suppressed by the engagement between the wire ring 45and the protrusion 46.

[0116]FIG. 27 shows imbedding a filament-type of wire material 47 intothe end in the axial direction of the clutch retainer 28 a such that itis engaged with a protrusion 46 that is formed on the end in the radialdirection of the roller 26.

[0117]FIG. 28 shows a spring 48 that is placed between the wire ring 45and the protrusion 46 in the example shown in FIG. 26, so as to apply anelastic force on the roller 26 in the radial direction of the clutchretainer 28 a.

[0118]FIG. 29 shows concave sections 49 that are formed on the innerperipheral surface on both ends in the axial direction inside the pocket31 that is formed in the clutch retainer 28 a, such that both of thepointed end sections in the axial direction of the roller 26 are fittedinto these concave sections 49.

[0119] When performing the method of assembling the pulley apparatuswith built-in roller clutch of this invention, before pushing the likeof the inner clutch ring into the inner-diameter side of the rollers,the rollers can be simultaneously moved using a jig 50 as shown in FIG.30 against the springs, and simultaneously moved to a specified positionin the circumferential direction of the retainer. The jig 50 that isused in this case, has an uneven surface that is substantially the sameas the cam surface that is formed around the outer peripheral surface ofthe like of the inner clutch ring, and has a fitted section that isengaged with the fitting section of the clutch retainer (for example theconcave sections of the uneven surface that is similar to the camsurface), and it has a chamfered section 51 that is formed around theouter peripheral edge on the end in the axial direction. Also, this jig50 is pushed into the inner-diameter side of the roller before the likeof the inner clutch ring is done, and simultaneously moves the rollersin the circumferential direction against the elastic force of thesprings, and moves the rollers to a specified position in thecircumferential direction between the inner peripheral surface of thelike of the outer clutch ring and the outer peripheral surface of thelike of the inner clutch ring. With the jig 50 keeping the rollers atthis specified position, the like of the inner clutch ring is pushedinto the inner-diameter side of the rollers, and then the jig 50 isremoved from the inner-diameter side of the rollers. It is also possiblefor the direction that the jig and the like of inner clutch ring arepushed into the inner-diameter side of these rollers to be in theopposite direction (pushed in from the opposite side in the axialdirection) or in the same direction. In either case, the jig is pushedout from the inner-diameter side of the rollers as the like of innerclutch ring is pushed into the inner-diameter side of the rollers. Whenperforming assembly using this kind of jig, it is not always necessaryto form the chamfered sections on the ends in the axial direction of therollers and on the outer peripheral edge on one end in the axialdirection of the like of inner clutch ring (they are unnecessary but canstill be formed).

INDUSTRIAL APPLICATION

[0120] This invention is constructed and functions as described above,and provides an assembly method for assembling a pulley apparatus withbuilt-in roller clutch easily while at the same time adequatelymaintaining durability and reliability.

1. A method of assembling a pulley apparatus with built-in roller clutchwhich, for use in belt transmission of an engine auxiliary equipment,comprises: a pulley, a shaft member located on the inner-diameter sideof the pulley, a roller clutch provided between the pulley and the shaftmember, a first ball bearing provided between the pulley and the shaftmember at one side thereof in the axial direction and a second ballbearing provided between the pulley and the shaft member at the otherside thereof in the axial direction, the roller clutch comprising: anouter-diameter section provided on the inner peripheral section of thepulley, an inner-diameter section provided on the outer peripheralsection of the shaft member and having an outer peripheral surfaceprovided with a cum section, a retainer provided between theouter-diameter section and the inner-diameter section and having aplurality of pockets, rollers held on the inside of the respectivepockets, and a plurality of springs engaged with the retainer to pushthe rollers, respectively, wherein the roller clutch is adapted to belocked in one rotational direction and unlocked in the other rotationaldirection, the first ball bearing comprising an outer-diameter section,inner-diameter section and a plurality of first balls, theouter-diameter section being located in the inner peripheral section ofthe pulley and having an inner peripheral surface formed with a firstouter-ring raceway, the inner-diameter section being located in theouter peripheral section of the rotating shaft and having an outerperipheral surface formed with a first inner-ring raceway, and the firstballs being provided between the first inner-ring raceway and the firstouter-ring raceway, the second ball bearing comprising an outer race,inner race and a plurality of second balls, the outer race being fittedto the inner peripheral surface of the pulley and having an innerperipheral surface formed with a second outer-ring raceway, the innerrace being fitted onto the outer peripheral surface of the shaft memberand having an outer peripheral surface formed with a second inner-ringraceway, and the second balls being provided between the secondinner-ring raceway and the second outer-ring raceway, wherein the innerrace and the shaft member form a shaft member unit, the inner-diametersection of the roller clutch having a first engagement section to beengaged with the retainer of the roller clutch, the retainer of theroller clutch having a second engagement section to be engaged with thefirst engagement section of the inner-diameter section of the rollerclutch, and a fall-out-prevention means for the rollers, the shaftmember unit having a plurality of step sections such that two of thestep sections are formed to provide a means to regulate movement in theaxial direction of the retainer of the roller clutch, the roller clutchhaving a chamfered section formed on at least one of the ends of therollers and the outer peripheral edge of the inner-diameter section, themethod comprising holding the rollers inside the pockets that are formedin the retainer of the roller clutch, pressing the rollers with thesprings which are engaged with the retainer, and then installing theretainer on the inner-diameter side of the outer-diameter section of theroller clutch to form an assembly, then engaging the second engagementsection of the retainer in the assembly with the first engagementsection of the inner-diameter section of the roller clutch ring, so thatrelative rotation between the inner-diameter section and the retainer isprevented, inserting the inner-diameter section of the roller clutchunder the rollers of the assembly by way of the chamfered section tosimultaneously compress the springs, and then installing the second ballbearing between the inner peripheral surface of the pulley and the outerperipheral surface of the shaft member.
 2. A method of assembling apulley apparatus with built-in roller clutch of claim 1 wherein the sumof the chamfering amount at the end of the rollers and the chamferingamount of the outer peripheral portion of the cum section is larger thanthe amount of protrusion of the rollers into the inner-diameter side ofthe inner-diameter section from the outer peripheral surface of theinner-diameter section in the state where the retainer of the assemblyis provided coaxial with the inner-diameter section, and where thesecond engagement section of the retainer is engaged with the firstengagement section of the inner-diameter section.
 3. A method ofassembling a pulley apparatus with built-in roller clutch which, for usein a belt transmission of an engine auxiliary equipment, comprises apulley, a shaft member provided on the inner diameter side of thepulley, a roller clutch provided between the pulley and the shaftmember, a first ball bearing provided between the pulley and the shaftmember at one side thereof in the axial direction, and a second ballbearing provided between the pulley and the shaft member at the otherside thereof in the axial direction, the roller clutch comprising anouter-diameter section provided in the inner peripheral section of thepulley, an inner-diameter section provided in the outer peripheralsection of the shaft member and having an outer peripheral surfaceformed with a cum section, a retainer provided between theouter-diameter section and the inner-diameter section and having aplurality of pockets, rollers held within the pockets and springsengaged with the retainer to press the rollers, and wherein the rollerclutch is locked in one rotational direction and unlocked in the otherrotational direction, the first ball bearing comprising anouter-diameter section provided in the inner peripheral section of thepulley and having an inner peripheral surface formed with a firstouter-ring raceway, an inner-diameter section provided in the outerperipheral portion of the shaft member and having an outer peripheralsurface formed with a first inner-ring raceway, and a plurality of firstballs provided between the first inner-ring raceway and the firstouter-ring raceway, the second ball bearing comprising an outer racefitted into the inner peripheral section of the pulley and having aninner peripheral surface formed with a second outer-ring raceway, aninner race fitted onto the outer peripheral section of the shaft memberand having an outer peripheral surface formed with a second inner-ringraceway, and a plurality of balls provided between the second inner-ringraceway and the second outer-ring raceway, wherein the shaft member andthe inner race form a shaft member unit, the inner-diameter section ofthe roller clutch having a first engagement section to be engaged withthe retainer of the roller clutch, the retainer of the roller clutchhaving a second engagement section to be engaged with the firstengagement section of the inner-diameter section of the roller clutch,and a fall-off-prevention means for the rollers, and the shaft memberunit having a plurality of step sections such that the displacement inthe axial direction of the retainer of the roller clutch is regulatedwith two of the step sections, the method comprising holding the rollersin the pockets of the retainer of the roller clutch, pressing therollers by the springs engaged with the retainer, and in this state,installing the retainer on the inner-diameter side of the outer-diametersection of the roller clutch to form an assembly, providing a jig whichhas substantially the same outside shape to the shape of theinner-diameter section of the roller clutch and has a chamfered sectionon the side of insertion into the assembly to simultaneously compressthe springs, using the chamfered portion to temporarily insert the jigunder the rollers in the assembly to simultaneously compress thesprings, engaging the second engagement section of the retainer of theassembly with the first engagement section of the inner-diameter sectionof the roller clutch, then inserting the inner-diameter section of theroller clutch on the inner diameter side of the assembly, and installingthe second ball bearing between the inner peripheral surface of thepulley and the outer peripheral surface of the shaft member.
 4. Themethod of assembling the pulley apparatus with built-in roller clutch ofany one of claims 1 to 3 wherein the installation of the second ballbearing between the pulley and the shaft member is made through anymeans selected from the group of pressing-in, crimping, welding andbonding.
 5. A pulley apparatus with built-in roller clutch for use inbelt transmission of an engine auxiliary equipment comprising a pulley,a shaft member provided on the inner diameter side of the pulley, aroller clutch provided between the pulley and the shaft member, a firstball bearing provided between the pulley and the shaft member at oneside thereof in the axial direction, and a second ball bearing providedbetween the pulley and the shaft member at the other side thereof in theaxial direction, the roller clutch comprising an outer-diameter sectionprovided in the inner peripheral section of the pulley, aninner-diameter section provided in the outer peripheral section of theshaft member and having an outer peripheral surface formed with a cumsection, a retainer provided between the outer-diameter section and theinner-diameter section and having a plurality of pockets, rollers heldwithin the pockets, and springs engaged with the retainer to press therollers, and wherein the roller clutch is locked in one rotationaldirection and unlocked in the other rotational direction, the first ballbearing comprising an outer-diameter section provided in the innerperipheral section of the pulley and having an inner peripheral surfaceformed with a first outer-ring raceway, an inner-diameter sectionprovided in the outer peripheral section of the shaft member and havingan outer peripheral surface formed with a first inner-ring raceway, anda plurality of balls provided between the first inner-ring raceway andthe first outer-ring raceway, the second ball bearing comprising anouter race being fitted into the inner peripheral surface of the pulleyand having an inner peripheral surface formed with a second outer-ringraceway, an inner race fitted onto the outer peripheral surface of theshaft member and having an outer peripheral surface formed with a secondinner-ring raceway, and a plurality of balls provided between the secondinner-ring raceway and the second outer-ring raceway, wherein the shaftmember and the inner race form a shaft member unit, the retainer of theroller clutch having a fall-off-prevention means for the rollers, theshaft member unit having a plurality of step sections such that thedisplacement in the axial direction of the retainer of the roller clutchis regulated with two of the step sections, and wherein the rollerclutch has a chamfered section formed on at least one of the end of therollers of the roller clutch and the outer peripheral edge of theinner-diameter section to simultaneously compress the springs.
 6. Thepulley apparatus with built-in roller clutch of claim 5 wherein the sumof the chamfering amount at the end of the rollers and the chamferingamount at the outer peripheral portion of the cum section is larger thanthe amount of protrusion of the roller into the inner-diameter side ofthe inner-diameter section from the outer peripheral surface of the cumsection of the inner-diameter section in the state where the retainer ofthe assembly is provided coaxial with the inner-diameter section, andwhere the second engagement section of the retainer is engaged with thefirst engagement section of the inner-diameter section.
 7. The pulleyapparatus with built-in roller clutch of any one of claims 5 to 6wherein the installation of the second ball bearing between the pulleyand the shaft member is made through any means selected from the groupof pressing-in, crimping, welding and bonding.